Thus, corn was born

The topic has been debated for a long time. We now know that a key event took place 5,000 years ago on the American continent: teosinte (a grass already grown there) hybridized with another to create an even more vigorous and nutritious plant, from which all current corn plants are derived.

It’s the story of an unlikely encounter that changed the face of the world – knowing that hybrid vigor remains at the heart of approaches to creating new varieties of maize today. Hervé Poirier, editor-in-chief of the scientific journal epsilon, explain to us today we finally understood how corn was born.

franceinfo: The key moment would have taken place about 5,000 years ago, on the plains of Mexico?

Hervé Poirier: It is the first cereal cultivated in the world, before rice and wheat. It has long been a staple food of Native Americans. But’ the origin of corn seemed a bit magical. What is this plant unlike any other, composed of a long stem, with heavy spikes, full of huge grains?

Where did this botanical monster come from?

After numerous hypotheses and numerous controversies, a consensus gradually emerged around the plant which is normally bush-shaped PUSH teosinte.

This was demonstrated in 2011: i About 10,000 years ago on the plains of Mexico, the teosinte plant underwent a gene mutation that transformed it into a long stem with grains stacked into pods. And this primitive form of corn began to be domesticated in Central America. But that wasn’t the end of the story.

By analyzing more than 1,000 different maize and teosinte genomes, a team of about thirty geneticists, mainly Chinese, has just shown that the key moment actually happened afterwards, during the hybridization that this mutant teosinte underwent between 4 and 6,000 years ago.

And hybridization? Does this mean interbreeding with another species?

Yes, with a different form of teosinte, adapted to altitudes, which has retained its bushy shape. And this chance encounter was magical: L The hybrid that was born from it created a stem-shaped plant, even more powerful and nutritious, with larger ears and enriched nutrient content. Better: this hybrid blooms earlier, making it adaptable to a cooler and more diverse climate than the plains of Mexico. In short: a monster was born.

And he thrived…

Nothing could stop the monster. It was this hybridization that allowed maize to spread beyond Central America, to invade the entire northern and southern continents. Then Christopher Collomb imported it to Europe in 1493.

In the course of hybridizations, this time artificial, farmers and seed companies continued to produce new varieties of corn. But yes: all corn plants grown today come from this original hybrid. They all come from this unlikely meeting of two teosintes between 4 and 6,000 years ago in the highlands of Mexico. The meeting that changed the face of the world.